We present the results of our analysis of cosmic-ray electrons using about 8×10<SUP>6</SUP> electron candidates detected in the first 12 months on-orbit by the Fermi Large Area Telescope. This work extends our previously published cosmic-ray electron spectrum down to 7 GeV, giving a spectral range of approximately 2.5 decades up to 1 TeV. We describe in detail the analysis and its validation using beam-test and on-orbit data. In addition, we describe the spectrum measured via a subset of events selected for the best energy resolution as a cross-check on the measurement using the full event sample. Our electron spectrum can be described with a power law ∝E<SUP>-3.08±0.05</SUP> with no prominent spectral features within systematic uncertainties. Within the limits of our uncertainties, we can accommodate a slight spectral hardening at around 100 GeV and a slight softening above 500 GeV.

Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV

BONAMENTE, EMANUELE;CECCHI, Claudia;S. Germani;TOSTI, Gino;
2010

Abstract

We present the results of our analysis of cosmic-ray electrons using about 8×106 electron candidates detected in the first 12 months on-orbit by the Fermi Large Area Telescope. This work extends our previously published cosmic-ray electron spectrum down to 7 GeV, giving a spectral range of approximately 2.5 decades up to 1 TeV. We describe in detail the analysis and its validation using beam-test and on-orbit data. In addition, we describe the spectrum measured via a subset of events selected for the best energy resolution as a cross-check on the measurement using the full event sample. Our electron spectrum can be described with a power law ∝E-3.08±0.05 with no prominent spectral features within systematic uncertainties. Within the limits of our uncertainties, we can accommodate a slight spectral hardening at around 100 GeV and a slight softening above 500 GeV.
2010
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11391/995207
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